Add fuelish API; protect the host against memory exhaustion

- fuelish role: receipt OCR API at fuelish.ladkau.de, API-key auth, shared
  Ollama model and request options
- base: 4 GB swap file; act_runner: job containers capped at 4 GB without swap
- docs and vault/service checks updated

ansible/roles/dashboard/templates/app.py.j2

@@ -25,6 +25,7 @@ SERVICES = [
     ("k8s",          "https://{{ domain_k8s }}",                200, "https://{{ domain_k8s }}"),
     ("Vaultwarden",  "https://{{ domain_vault }}",             200, "https://{{ domain_vault }}"),
     ("Downloads",    "https://{{ domain_dl }}",               200, "https://{{ domain_dl }}"),
+    ("Fuelish",     "https://{{ domain_fuelish }}/health",   200, "https://{{ domain_fuelish }}/health"),
     ("AI Chat",      "https://{{ domain_n8n }}/chat",         401, "https://{{ domain_n8n }}/chat"),
     ("n8n",          "https://{{ domain_n8n }}",              401, "https://{{ domain_n8n }}"),
 ]